Orchestrated membrane remodeling creates flows of substance and information to sustain the lifecycle of a cell. Therefore understanding the molecular mechanisms that cells use to generate, maintain and deform the membrane structures has been a central task of cell biology. Cell-free experiments provide a clean system to study the functional interactions between the biomolecules that mediate the cell membrane remodeling. However, most of previous in vitro studies lack the precise control of the physical and chemical properties of the membrane (e.g. membrane vesicle's size and shape; local density and spatial organization of membrane- associating proteins), thus leaving considerable room of ambiguity. We hypothesize that we could engineer membrane remodeling events with a high level of control and further elucidate the molecular mechanisms for cell membrane dynamics by setting up in vitro scenarios in which the membrane modulating elements are precisely organized on DNA nanostructures. In other words, we plan to dissect the membrane trafficking machineries by artificially placing their natural components on a programmable nano-template. We propose to use this transformative approach to study the underlying mechanism of SNARE mediated membrane fusion as well as the membrane curvature sensing/inducing activities of BAR-domain proteins. Beyond the goals set by this proposal, we believe our project could open doors for new therapeutic strategies for membrane trafficking related diseases as well as efficient drug-delivery nanomachines.